No changes made to any config file

I have a rather small (well Large) problem where any changes made in ISPConfig aren't written to any config file. New sites aren't setup and DNS entries aren't setup or removed properly. I've looked for ispconfig.log but that doesn't exisit. Any ideas?

Writeconf.php has just failed on a segmenation fault!!! took 4 minutes to come through - I have also followed the php downgrade by Till

Most likely the permissions of the bind directories are wrong. Please reconfigure bind as described in the perfect setup guide for your linux distribution. Downgrading PHP is not nescessaery and not recommended for the current releases and may cause problems.

I've done that already and it made no difference. I understand that if the bind permissions were set incorrectly then ISPConfig wouldn't be able to right to bind files, But how does this stop it writing Apache files?

We have tried with a re-install over the orginial system and after moving all our clients to a different server tried a fresh install of ISPConfig. We have opted to start with a fresh base install, aiming this decision as a problem somewhere within the OS. I believe it maybe an system update that may have broke the system but can't be quite sure.